There's a gcc option -Wsuggest-attribute that, as it says, suggests some function attributes to provide some hints and allowing more optimizations.
Debug build text data bss dec hex filename 1514058 146768 27496 1688322 19c302 pre/btrfs.ko 1512603 146736 27496 1686835 19bd33 post/btrfs.ko DELTA: -1455 Release build text data bss dec hex filename 1079288 17316 14912 1111516 10f5dc pre/btrfs.ko 1078138 17316 14912 1110366 10f15e post/btrfs.ko DELTA: -1150 David Sterba (3): btrfs: add __cold attribute to more functions btrfs: add const function attribute btrfs: add __pure attribute to functions fs/btrfs/async-thread.c | 6 ++---- fs/btrfs/async-thread.h | 4 ++-- fs/btrfs/ctree.c | 2 +- fs/btrfs/ctree.h | 6 +++--- fs/btrfs/dev-replace.c | 2 +- fs/btrfs/dev-replace.h | 2 +- fs/btrfs/disk-io.c | 4 ++-- fs/btrfs/disk-io.h | 4 ++-- fs/btrfs/ioctl.c | 2 +- fs/btrfs/space-info.c | 2 +- fs/btrfs/space-info.h | 2 +- fs/btrfs/super.c | 4 ++-- fs/btrfs/volumes.c | 4 ++-- fs/btrfs/volumes.h | 2 +- 14 files changed, 22 insertions(+), 24 deletions(-) -- 2.23.0
